96 TERNSTROMIACEiE. 



are four or five genera of few species, among which are the familiarly known 

 and most important plants of the order, the Tea and the Camellia. The re- 

 maining and much larger portion of the order belongs almost without excep- 

 tion to Tropical America and Southeastern Asia. Of the sensible qualities of. 

 the tropical species little is known, except that their bark is astringent and 

 sometimes used by the tanner, and their buds and young leaves are muci- 

 laginous. The properties of tea, which is prepared from the young leaves 

 of two species, or perhaps varieties, of Thea, are well known. The infu- 

 sion contains mucilage, a bitter extractive, resin, gallic acid, tannin, and a 

 peculiar highly azotized substance called iheine, on which, and on an ethe- 

 real subnarcotic principle, its grateful and slightly stimulating properties 

 depend. The Tea-plant belongs to a temperate region ; when cultivated in 

 a hot climate, as at Penang, its mildly stimulating properties are said to be- 

 come narcotic. The Camellia is scarcely if at all distinguishable as a genus 

 from Thea, and doubtless is endowed with very similar qualities. From the 

 fleshy embryo of the seeds, especially of Camellia oleifera, an excellent 

 table oil is expressed. 



